1 files changed, 19 insertions, 0 deletions
diff --git a/src/test/ui/closures/2229_closure_analysis/diagnostics/cant-mutate-imm-borrow.rs b/src/test/ui/closures/2229_closure_analysis/diagnostics/cant-mutate-imm-borrow.rs
new file mode 100644
index 000000000..77effcb00
--- /dev/null
+++ b/src/test/ui/closures/2229_closure_analysis/diagnostics/cant-mutate-imm-borrow.rs
@@ -0,0 +1,19 @@
+// edition:2021
+
+// Test that if we deref an immutable borrow to access a Place,
+// then we can't mutate the final place.
+
+fn main() {
+    let mut x = (format!(""), format!("X2"));
+    let mut y = (&x, "Y");
+    let z = (&mut y, "Z");
+
+    // `x.0` is mutable but we access `x` via `*z.0.0`, which is an immutable reference and
+    // therefore can't be mutated.
+    let mut c = || {
+    //~^ ERROR: cannot borrow `*z.0.0` as mutable, as it is behind a `&` reference
+        z.0.0.0 = format!("X1");
+    };
+
+    c();
+}